PASADENA, California (CNN) --The robotic explorer Spirit woke up to its first full day on Mars on Sunday, hours after making a perilous landing, sending postcards to Earth and taking a much deserved snooze.

The $400 million NASA craft, the first to land without disaster on the red planet since 1997, probably woke up around 5:30 p.m. ET Sunday.

That was a few hours after Martian dawn, when the sun's rays juiced up its solar panels enough for it to wake itself up, according to the space agency.

Just to make sure, mission controllers sent a transmission of the Beatles' tune "Good Morning, Good Morning" to perk up the rover, which probably will not speak for a few hours while it warms up, NASA said.

The six-wheeled robot ship, crammed with high-tech cameras and geology instruments, is expected to begin roaming the surface in a week or so, after it has a chance to stretch, stand up and settle into its new environment.

The rover by all accounts made a nearly flawless landing late Saturday, far surpassing even the most optimistic predictions of precision to hit its landing target in Gusev Crater.

"Even some of the things that we were not sure about are working really well," said Brian Portock, a member of the navigation team at NASA's Jet Propulsion Laboratory in Pasadena.

'We're back'

Earlier in the day, soon after confirmation of the late Saturday landing, NASA chief Sean O'Keefe poured champagne and toasted Spirit's handlers.

"This is a big night for NASA. We're back," said O'Keefe, whose agency lost a Martian lander in 1999.

Within hours of touchdown, Spirit beamed back images from its new home, stunning black and white snapshots that elicited excited shouts from mission controllers.

Its mobile geologic studies are expected to last at least 90 days. It may send its first color images back Sunday night.

The golf cart-size Spirit went through what NASA assistant administrator Ed Weiler characterized as "six minutes from hell" -- the time it took to enter the Martian atmosphere, descend and land in Gusev Crater.

During the descent, Spirit deployed parachutes and fired retrorockets to decelerate. Seconds before impact, it inflated a protective cocoon of airbags. Everything went as planned.

"It went to perfection. I can't tell the difference between what was predicted and what actually happened," said Rob Manning, descent and landing manager at JPL.

A series of bounces and rolls may have sent the robot up to four stories high and more than a mile from its landing spot, according to mission control scientists at JPL. The final stopping spot has elated mission researchers.

"The rocks, to a great extent, look swept clean. It's a much cleaner surface than what we had a right to hope for," said Steven Squyres, a Cornell University geologist in charge of the scientific instruments on Spirit and its identical twin, Opportunity, which will complete the 300 million-mile trip to Mars in three weeks.

"It's a very good surface for driving. It couldn't be better for what this vehicle is designed for," he said.

Spirit launched June 10 and Opportunity took off July 7.

Stunning panoramas

Spirit and Opportunity have much more mobility and capability than the most recent successful visitor to Mars.

The 1997 Pathfinder mission included a lander, which beamed back thousands of images, and Sojourner, a toy-sized test rover that scurried around the rocks and boulders littering the landing site.

Each of the new rover twins, however, is built to explore nearly as much territory in one day as Sojourner covered in three months, about 100 yards.

And each comes equipped with eight cameras that should provide stunning panoramas of the Martian surface, with resolutions so sharp they retain crisp detail when blown up to the size of a movie screen, according to NASA.

Their microscopes, spectrometers and drills could unlock geologic secrets from billions of years ago, when scientists think the cold and dry planet may have been warm and wet enough to host life.